style xp, i personally like it better than windows blind. i don't like the windows blind themes. tmpgenc if you are into video stuff vlc media player to play videos mirc....for xdcc and chatting
Gspot or avicodec is helpful if your gonna burn stuff to DVD. Also VLC player will play lots of files without the codecs installed
My main essentials are mIRC, AIM, MSN, and FireFox. On Linux, gotta have X-Chat, or that means no IRC. Which means Spek goes crazy.
Windowblinds is a bloated P.O.S imo, use uxtheme.dll, and Uttorrent is mich better than azurues, I do like Limewire PRO, but another good p2p app is shareaza, its not java, it connects to gnutella1 (limewire)gnutella2(its own network) and edonkey2000.